Welcome

Where the 19th Century Art of Mirror Making Meets the 21st Century

The Saint Petersburg Mirror Lab is a small band of dedicated mirror grinders and telescope makers living in the Tampa Bay area of Florida. We offer a mirror making class for interested
persons. We strive to create the best mirrors our home brew technology can muster. This includes robotic foucault testing and laser interferometry.

Brad's Copper Clad Telescope2018-12-14

Brad covered his telescope with a thin layer of copper sheeting. Now he is using some copper stripto cover the seams. Here he is starting with the with the seam that goes the length of thetelescope. That will be followed with strips covering the seams that wrap around the circumferenceof the telescope.

Dave Grinding 12.5 Inch Mirror2018-11-25

Dave grinds his 12.5" mirror while Paul (left) and Bill offer their opinion of his technique.

Glass Floor Tile Becomes 8 Inch Mirror Blank2018-11-10

Mike bought a case of clear glass floor tiles and he used his kiln to make a test 8 inch mirrorblank out of one.

Brad refinishing his telescope2018-11-10

Brad is smoothing his altitude bearings before refinishing them. His scope should be well tunedbefore the Orange Blossom Special (OBS) Star Party in January 2019.

Pauls Drum Shell Telescope Update2018-11-10

Paul with the help of Mike is cutting a circle out of some Baltic Birch plywood to fit his 16 inchdrum shell telescope. During the test fit he looks pretty pleased with the results.

Bath Interferometer2018-05-10

Paul McNabb built a Bath Interferometer and lab members have begun
experimenting with a mirror thatwas finished using the Foucault
tester. The test uses a laser, beam splitter and a couple oflenses to
create fringes from the mirror's shape. An image of these fringes is
processed by aprogram appropriately called 'Fringe' that creates a 2D
color topography of the mirror showing highand low areas relative to
the perfect parabola for that mirror's diameter and f-ratio.

The 8" f3 Mirror is coming along2018-04-08

This is a lab staff project and we are taking turns working on whet will become a 8" f3 mirror. Ron(left) is hogging it out at about the 152 thousandths depth with a goal of 166K. Right is a closeup of Ralph working on it with the used 80 grit becoming mud around the tool. We finished the dayright on the depth and we will be moving to 120 grit next week.

Paul's drum shell2018-02-18

Paul is using a drum shell for the mirror box. Here he is preparing to cut the shell shorter. Theshell is on a sled over Ralph's table saw. The square plywood is used to prevent the shell frommoving sideways on the sled. The shell was rotated while the saw ws running. This was a three manoperation. The amazing thing was that it worked and made a beautiful cut.

Deep Core Samples2018-02-03

The optical lab gang often enjoys science that diverges a bit from telescope making. Lately Geologyand fossil hunting have been popular. Here are some deep core samples from Manatee County.

Mike's 12.5" Cast Aluminum Mirror Cell2018-01-18

After casting the 12.5" honeycomb mirror with pin holes for a mirror cell Mike cast an aluminum cellusing the lost foam method. The floatation cell uses felt pads and heat shrink tubing to protectthe mirror from direct contact with the aluminum.